Exclude one or more variable´s options from output in proc tabulate

Hello, My doubt is the follow. I have one question (variable) that has three option.
I´d like to calculate the percentage of firms by region that mark option "1".
This I can do, but I dind´t get that the other two option are exclude of output.
The example below illustrate the case.

Re: Exclude one or more variable´s options from output in proc tabulate

sorry, out of practise - I forgot the important feature to mention and demo :
A percentage can be derived as [pre]
sum( of analysis varA )
100 * ---------------------------
sum( of analysis varB )[/pre] with small change like: [pre]
data prepare/view=prepare ;
set answers ;
* your original data set of answers ;
q176_1 = (q176=1) ;
q176_2 = (q176=2) ;
q176_3 = (q176=3) ;
retain one 1 ;
run;
proc tabulate data= prepare ;
var q176_1 one;
class region ;
table ( region all), q176_1='Q176'
* pctsum='1' * f=5.2
n='all'*f=7.
/ rts= 20 ;
run;
[/pre] try that approach....
At the back of my mind I feel the introduction of the "one" variable should be unneccessary, perhaps using pctn.
However, the important addition here is that using an analysis variable as percentage denominator definition, gives you a ratio of two analysis variables instead of the summary of each value of the class variable.